Machine Learning Methods in the Environmental Sciences
Neural Network and Kernels

Exercise 1.4

From the given data file (Ex1_4_corr) in Matlab format or text format, compare the Pearson correlation with the Spearman rank correlation for the time series x and y (each with 40 observations). Repeat the comparison for the time series x2 and y2 (from the same data file as above), where x2 and y2 are the same as x and y, except that the 5th data point in y is replaced by an outlier in y2. Repeat the comparison for the time series x3 and y3, where x3 and y3 are the same as x and y, except that the 5th data point in x and y is replaced by an outlier in x3 and y3. Make scatterplots of the data points in the x-y space, the x2-y2 space and the x3-y3 space. Also plot the linear regression line in the scatterplots.

Exercise 1.5

Using the given data file (Ex1_5_MLR) in Matlab format or text format, perform multiple linear regression with predictors x1, x2 and x3, and the response variable y. Rank the importance of the predictors in their influence on y.


William W. Hsieh
2009